Patents by Inventor Norio Hirashita

Norio Hirashita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8183643
    Abstract: A semiconductor device includes diffusion layers formed in a SOI layer under a side-wall, a channel formed between the diffusion layers, silicide layers sandwiching the diffusion layers wherein interface junctions between the diffusion layers and the silicide layers are (111) silicon planes.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: May 22, 2012
    Assignee: Oki Semiconductor Co., Ltd.
    Inventors: Takashi Ichimori, Norio Hirashita
  • Publication number: 20110223724
    Abstract: A semiconductor device includes diffusion layers formed in a SOI layer under a side-wall, a channel formed between the diffusion layers, silicide layers sandwiching the diffusion layers wherein interface junctions between the diffusion layers and the silicide layers are (111) silicon planes.
    Type: Application
    Filed: May 17, 2011
    Publication date: September 15, 2011
    Applicant: OKI SEMICONDUCTOR CO., LTD.
    Inventors: Takashi Ichimori, Norio Hirashita
  • Patent number: 7759228
    Abstract: A method of manufacturing a semiconductor device. In the method, a substrate is prepared, which includes a buried oxide film and a SiGe layer formed on the buried oxide film. Then, heat treatment is performed on the substrate at a temperature equal to or lower than a first temperature, to form a protective oxide film on a surface of the SiGe layer. Next, the substrate having the protective oxide film is heated in a non-oxidizing atmosphere to a second temperature higher than the first temperature. Further, heat treatment is performed on the substrate thus heated, in an oxidizing atmosphere at a temperature equal to or higher than the second temperature, to form oxide the SiGe layer, make the SiGe layer thinner and increasing Ge concentration in the SiGe layer, thus forming a SiGe layer having the increased Ge concentration.
    Type: Grant
    Filed: June 9, 2006
    Date of Patent: July 20, 2010
    Assignees: Kabushiki Kaisha Toshiba, Oki Electric Industry Co., Ltd.
    Inventors: Naoharu Sugiyama, Norio Hirashita, Tsutomu Tezuka
  • Patent number: 7479682
    Abstract: A field effect transistor having metallic silicide layers is formed in a semiconductor layer on an insulating layer of an SOI substrate. The metallic silicide layers are composed of refractory metal and silicon. The metallic silicide layers extend to bottom surfaces of source and drain regions. A ratio of the metal to the silicon in the metallic silicide layers is X to Y. A ratio of the metal to the silicon of metallic silicide having the lowest resistance among stoichiometric metallic silicides is X0 to Y0. X, Y, X0 and Y0 satisfy the following inequality: (X/Y)>(X0/Y0).
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: January 20, 2009
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Norio Hirashita, Takashi Ichimori
  • Patent number: 7244996
    Abstract: A field effect transistor having metallic silicide layers is formed in a semiconductor layer on an insulating layer of an SOI substrate. The metallic silicide layers are composed of refractory metal and silicon. The metallic silicide layers extend to bottom surfaces of a source and a drain regions. A ratio of the metal to the silicon in the metallic silicide layers is X to Y. A ratio of the metal to the silicon of metallic silicide having the lowest resistance among stoichiometaric metallic silicides is X0 to Y0. X, Y, X0 and Y0 satisfy the following inequity: (X/Y)>(X0/Y0).
    Type: Grant
    Filed: April 5, 2001
    Date of Patent: July 17, 2007
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Norio Hirashita, Takashi Ichimori
  • Publication number: 20070158757
    Abstract: A field effect transistor having metallic silicide layers is formed in a semiconductor layer on an insulating layer of an SOI substrate. The metallic silicide layers are composed of refractory metal and silicon. The metallic silicide layers extend to bottom surfaces of source and drain regions. A ratio of the metal to the silicon in the metallic silicide layers is X to Y. A ratio of the metal to the silicon of metallic silicide having the lowest resistance among stoichiometric metallic silicides is X0 to Y0. X, Y, X0 and Y0 satisfy the following inequality: (X/Y)>(X0/Y0).
    Type: Application
    Filed: February 28, 2007
    Publication date: July 12, 2007
    Inventors: Norio Hirashita, Takashi Ichimori
  • Patent number: 7199030
    Abstract: An impurity is ion-implanted with a silicon nitride film formed on a silicon substrate as a mask film to form a source/drain layer of a MOS transistor. Heat treatment for activating the impurity is done as it is without removing the silicon nitride film to thereby produce heat treatment-based stress between the silicon nitride film and the silicon substrate.
    Type: Grant
    Filed: May 28, 2003
    Date of Patent: April 3, 2007
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Satoshi Ikeda, Yutaka Kamata, Ikuo Kurachi, Norio Hirashita
  • Publication number: 20060281234
    Abstract: A method of manufacturing a semiconductor device. In the method, a substrate is prepared, which includes a buried oxide film and a SiGe layer formed on the buried oxide film. Then, heat treatment is performed on the substrate at a temperature equal to or lower than a first temperature, to form a protective oxide film on a surface of the SiGe layer. Next, the substrate having the protective oxide film is heated in a non-oxidizing atmosphere to a second temperature higher than the first temperature. Further, heat treatment is performed on the substrate thus heated, in an oxidizing atmosphere at a temperature equal to or higher than the second temperature, to form oxide the SiGe layer, make the SiGe layer thinner and increasing Ge concentration in the SiGe layer, thus forming a SiGe layer having the increased Ge concentration.
    Type: Application
    Filed: June 9, 2006
    Publication date: December 14, 2006
    Inventors: Naoharu Sugiyama, Norio Hirashita, Tsutomu Tezuka
  • Publication number: 20060145271
    Abstract: A semiconductor device includes diffusion layers formed in a SOI layer under a side-wall, a channel formed between the diffusion layers, silicide layers sandwiching the diffusion layers wherein interface junctions between the diffusion layers and the silicide layers are (111) silicon planes.
    Type: Application
    Filed: March 6, 2006
    Publication date: July 6, 2006
    Inventors: Takashi Ichimori, Norio Hirashita
  • Patent number: 6861322
    Abstract: A heat treatment for diffusing impurity ions implanted into a silicon layer is performed at a heat treatment temperature which is less than an aggregation temperature of the silicon layer. A thermal aggregation of the silicon layer can be inhibited, thereby reducing a silicon deficiency of the silicon layer.
    Type: Grant
    Filed: May 28, 2002
    Date of Patent: March 1, 2005
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Norio Hirashita, Takashi Ichimori, Toshiyuki Nakamura
  • Patent number: 6750088
    Abstract: A device isolation region made up of a silicon oxide film, which is perfectly isolated up to the direction of the thickness of an SOI silicon layer, and an activation region of the SOI silicon layer, whose only ends are locally thinned, are formed on an SOI substrate. A source diffusion layer and a drain diffusion layer of a MOS field effect transistor in the activation region are provided so that according to the silicidization of the SOI silicon layer subsequent to the formation of a high melting-point metal, a Schottky junction is formed only at each end of the activation region and a PN junction is formed at a portion other than each end thereof.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: June 15, 2004
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Norio Hirashita, Takashi Ichimori
  • Publication number: 20040067626
    Abstract: An impurity is ion-implanted with a silicon nitride film formed on a silicon substrate as a mask film to form a source/drain layer of a MOS transistor. Heat treatment for activating the impurity is done as it is without removing the silicon nitride film to thereby produce heat treatment-based stress between the silicon nitride film and the silicon substrate.
    Type: Application
    Filed: May 28, 2003
    Publication date: April 8, 2004
    Inventors: Satoshi Ikeda, Yutaka Kamata, Ikuo Kurachi, Norio Hirashita
  • Publication number: 20030151094
    Abstract: A device isolation region made up of a silicon oxide film, which is perfectly isolated up to the direction of the thickness of an SOI silicon layer, and an activation region of the SOI silicon layer, whose only ends are locally thinned, are formed on an SOI substrate. A source diffusion layer and a drain diffusion layer of a MOS field effect transistor in the activation region are provided so that according to the silicidization of the SOI silicon layer subsequent to the formation of a high melting-point metal, a Schottky junction is formed only at each end of the activation region and a PN junction is formed at a portion other than each end thereof.
    Type: Application
    Filed: January 15, 2003
    Publication date: August 14, 2003
    Inventors: Norio Hirashita, Takashi Ichimori
  • Patent number: 6531743
    Abstract: A device isolation region made up of a silicon oxide film, which is perfectly isolated up to the direction of the thickness of an SOI silicon layer, and an activation region of the SOI silicon layer, whose only ends are locally thinned, are formed on an SOI substrate. A source diffusion layer and a drain diffusion layer of a MOS field effect transistor in the activation region are provided so that according to the silicidization of the SOI silicon layer subsequent to the formation of a high melting-point metal, a Schottky junction is formed only at each end of the activation region and a PN junction is formed at a portion other than each end thereof.
    Type: Grant
    Filed: January 14, 2002
    Date of Patent: March 11, 2003
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Norio Hirashita, Takashi Ichimori
  • Publication number: 20020182784
    Abstract: A heat treatment for diffusing impurity ions implanted into a silicon layer is performed at a heat treatment temperature which is less than an aggregation temperature of the silicon layer. A thermal aggregation of the silicon layer can be inhibited, thereby reducing a silicon deficiency of the silicon layer.
    Type: Application
    Filed: May 28, 2002
    Publication date: December 5, 2002
    Inventors: Norio Hirashita, Takashi Ichimori, Toshiyuki Nakamura
  • Publication number: 20020036320
    Abstract: A semiconductor device includes diffusion layers formed in a SOI layer under a side-wall, a channel formed between the diffusion layers, silicide layers sandwiching the diffusion layers wherein interface junctions between the diffusion layers and the silicide layers are (111) silicon planes.
    Type: Application
    Filed: September 26, 2001
    Publication date: March 28, 2002
    Inventors: Takashi Ichimori, Norio Hirashita
  • Publication number: 20010028087
    Abstract: A field effect transistor having metallic silicide layers is formed in a semiconductor layer on an insulating layer of an SOI substrate. The metallic silicide layers are composed of refractory metal and silicon. The metallic silicide layers extend to bottom surfaces of a source and a drain regions. A ratio of the metal to the silicon in the metallic silicide layers is X to Y. A ratio of the metal to the silicon of metallic silicide having the lowest resistance among stoichiometaric metallic silicides is X0 to Y0. X, Y, X0 and Y0 satisfy the following inequity: (X/Y)>(X0/Y0).
    Type: Application
    Filed: April 5, 2001
    Publication date: October 11, 2001
    Inventors: Norio Hirashita, Takashi Ichimori
  • Patent number: 6274470
    Abstract: A protective layer is formed on a metallic silicide layer prior to a heat treatment for reducing a resistance of the metallic silicide layer. As a result, vertical growing of crystallization in the metallic silicide layer is restrained by the protective layer during the heat treatment. Moreover, the crystallization in the metallic silicide layer easily grows along the protective layer. Therefore, evenness of the metallic silicide layer can be maintained.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: August 14, 2001
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Takashi Ichimori, Norio Hirashita
  • Patent number: 6197601
    Abstract: In a semiconductor manufacturing apparatus, a semiconductor substrate ion-implanted with an ion species is heated and thereby raised in temperature under vacuum. At this time, a partial pressure of a gas released from the semiconductor substrate is measured by a quadrupole mass spectrometer. Further, a change in partial pressure with time is observed and compared with a pre-measured release characteristic, whereby the temperature of the semiconductor substrate is corrected.
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: March 6, 2001
    Assignee: OKI Electric Industry Co., Ltd.
    Inventor: Norio Hirashita
  • Patent number: 6037588
    Abstract: In order to achieve a method for analyzing the compositional distribution of deposited film adhering to the internal surface of a contact hole having a diameter in the deep submicron order, primary ions 18 are radiated into the surface 12a of an insulating film 12 where the contact hole 14 is formed to generate secondary ions 20. The primary ions are radiated into the surface of the insulating film from a constant diagonal direction. Then, mass spectrometry is performed on the resulting secondary ions to detect the compositional distribution of the deposited film 16 formed at the internal surface of the contact hole. Thus, the compositional distribution of the deposited film is ascertained over the depth-wise direction of the contact hole.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: March 14, 2000
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Guo-Lin Liu, Hidetsugu Uchida, Izumi Aikawa, Naokatsu Ikegami, Norio Hirashita